Double clutch transmission



Q E. FISHBURN T DOUBLE CLUTCH TRANSMISSION Filed Dec 27, 1952 16INVENTORS Ozzo E.Fz'sh12u rn and Palmer Ora,

Z1 ATTORNEYS Patented Apr. 20, 1937 UNITED STATES,

PATENT OFFICE DOUBLE CLUTCH ramsmssron tion of Illinois ApplicationDecember 27, 1932', SerialNo. 648,948

1 Claim.

Our invention relates to improvements in automobile transmissions. Ithas for one of its objects the provision of means for permitting of aneasy shift of gears of transmissions of the sliding gear type and moreparticularly it has for one of its objects the provision of means fordisconnecting certain of the gears of the transmission from drivingconnection with the driving shaft during the shifting of gears of thetransmission from one speed to the other.

For the purpose of disclosing the invention certain embodiments thereofare shown in the accompanying drawing, in which:

Fig. 1 is a side elevation partly in section of a transmission andclutch mechanism embodying the invention; and

Fig. 2 isalongitudinal sectional view of the transmission.

In the embodiment illustrated the transmission includes the usualtransmission housing I having a removable top cover 2. Into this housingextends a drive shaft 3 connected by a suitable engine clutch 4 of anyof ,the commercial types with the engine shaft. This shaft 3 is coaxialwith a driven shaft 5 extending into the transmission housing and havingits forward end 6 piloted in the rear end of the drive shaft 3.

This shaft 5 is provided with a sliding gear I and with a pair ofsliding gears 8 and 9, all of which gears are splined on the shaft 5.

Mounted below the shafts 3 and 5 is a countershaft l6 having rotatablymounted thereon a gear II and a spindle I2, which spindle is providedwith a series of gears l3, I4, and I5, and it will be noted that thegear H and spindle l2 are rotatably mounted on rollers l6 interposedtherebetween and the shaft l0, whereby these parts rotate on the shaft[0 with a minimum of frictional resistance. The gear ll meshes with agear I! on the driving shaft 3 and these gears are in constant mesh,whereby the gear H is constantly driven from the gear H. The gear 1, forhigh speed or direct drive, is adapted to be clutched with the gear I!and for second speed drive the gears l4 and 8 are adapted to be meshed.For low speed drive the gear 9 meshes with the gear l5. For reversedrive an idler gear (not shown) is adapted to be meshed with the gears 9and I5.

The hub l8 of the gear H is extended and is provided with radial clutchteeth l9 and the end of the spindle I2 is likewise provided with aseries of radially extending clutch teeth 26. These clutch teeth areadapted to be bridged by a ring clutch member 2| having internal teethmeshing with the teeth l9 and adapted to be meshed when the ring memberis slid to the right, looking at Fig. 2,, with the teeth 26; wherebywhen the clutch member 2| is moved into-engaging position, the spindle|-2 will be driven from the gear H. However, when the clutch member 2iis slid to the left, to'the limit of its movement, looking at Fig. 2,thespindle I2 will be disengaged from driving connection with the gearII and likewise disconnected from driving connection with the driveshaft 3, whereby during shifting movement the gears l3, l4, and I5 willbe disconnected from any power loadand in what may be termed a floatingcondition.

The gears 8 and 9 and l are shifted through the instrumentality of asuitable shift lever 22 adapted to engage shift rails 23 and these railscarry forks 24 and 25 engaging an annular groove in the hub of the gearI and the hub of the gears 8 and 9.

The engine clutch 4 is operated by the usual clutch pedal 26 which inthis instance is mounted on a shaft 21 carried by a bracket member 58.This clutch pedal 26 is provided with an extension or arm 28 connectedby an adjustable linkage member 29 with a lever 30 mounted on the shaft3|, arranged in the clutch housing by means of which shaft the lever 30is connected with the clutch operating arm 32, whereby when the clutchpedal 26 is depressed the engine clutch mechanism will be disengaged.

The sliding clutch ring 2| is operated by a clutch fork engaging in anannular groove in the ring and pivotally connected at 33 with a lever 34mounted on the interior of the casing on a shaft 35 and connected with asecond lever 35 mounted on said shaft on the exterior of the casing I.This lever 35 is connected by an adjustable link member 36 with a leverarm 31 which is connected with a bell crank lever arm 39. In thisinstance lever arms 31 and 39 are of integral construction and arepivotally mounted on shaft 38 supported by bracket 58. This arm 39 isprovided with a slot 40 which continues into a slot 4| extending at anangle to the slot 49. The purpose of this will appear more fullyhereinafter. Operating in the slot 40 is a pin 42 mounted on an arm 43carried by the shaft 21 and connected with the clutch pedal 26, so thatthe depression of the clutch pedal 26 will simultaneously rock the arm43.

In operation, when the clutch pedal 26 is depressed for the purpose ofdisengaging the clutch 4, this movement of the clutch pedal 26 will rockthe arm 43 causing the pin 42 to ride upwardly,

looking at Fig. 1, in the slot 40. During the movement of the pin 42 inthe slot 40 no movement will be imparted to the lever arm 39. As soonhowever as the pin 42 engages in the slot portion 4| during thedepressing movement of the clutch pedal 26, the arm 39 will be rocked onits stud shaft 33, the free end of the arm raising, and thereby rock thearm 3'! which in turn, through the link 36, rocks the arms 35 and 34thus shifting the clutch ring 2! to the left, looking at Figs. 1 and 2,and disengaging the spindle 12 from the gear II. It will be noted thatthe disengaging action of the clutch ring 2| takes place during thedisengaging movement of the pedal '26 but only after the engine clutchhas been disengaged.

When the clutch pedal 26 is permitted to move to engaging position, theinitial movement of this clutch pedal will also, through the rockingaction of the pin 42 in the slot 4|, move the clutch ring 2| intoengaging position. It will however be noted that during the latter partof the engaging movement of the clutch pedal 26 there will be a lostmotion connection between this clutch pedal and the clutch ring 2|.Therefore it is apparent that the connection between the clutch pedal 26and the clutch ring 2| is a lost motion connection during the initialdisengaging movement of the clutch pedal and a lost motion connectionduring the end of the engaging movement of the clutch pedal. This lostmotion is permitted since slot 40 is constructed in radial relation tothe center of shaft 21 and as a result, during movement of pin 42 inslot 40 no movement will be imparted to arm 39. This connectiontherefore permits of the disengagement of the engine clutch 4 prior tothe disengagement of the ring clutch 2i and an engagement of the ringclutch 2| prior to the engagement of the engine clutch 4.

We claim as our invention! In combination a transmission housing,transmission mechanism in said housing including a variable speed geartrain having a drive shaft, a driven shaft and means including acountershaft and a positive acting clutch for connecting anddisconnecting said drive shaft and. said driven shaft, an engine clutchmounted on said housing having its driven element connected with saiddrive shaft, a manually operated en- -gine clutch control memberpivotally mounted on said transmission housing, an operating connectionbetween said control member and said engine clutch, a rocker pivotallymounted on said housing and having arms extending away from the axisthereof, one arm of said rocker having a slot therein, one portion ofsaid slot extending at an angle to the remaining portion, means carriedby said control member adapted to ride in said slot, said slotted rockerarm being so arranged relative to said control member as to cause saidrocker to remain stationary during the first part of the engine clutchrelease movement of said control member and to move angularly upon itsaxis during the later part of said engine clutch release movement, arock-shaft mounted on said housing having an arm engaged with saidpositive acting clutch and a second arm located externally of thehousing and an adjustable link interconnecting the extremities of saidsecond rook-shaft arm and the remaining arm of said rocker wherebyangular movement of said rocker may cause said rock-shaft to moveangularly to actuate said positive clutch.

OTTO E. FISHBURN. PALMER ORR.

